I'm on Ubuntu 14.04 with SSMTP 2.64. I found that Gmail now has added an account setting called "Access for less secure apps". You can take the mail account that you are trying to reach, open it in Gmail, and then open a new tab and go to here:
https://myaccount.google.com/?pli=1 Scroll down and look for "Access for less secure apps". Make certain it says "Allowed". By default, it's now off. The link goes to here: https://www.google.com/settings/security/lesssecureapps?pli=1 If you don't do this, then SSMTP will fail, from my experience. However, intermittently I'm finding that it's failing with "Unable to set AuthPass" still and I don't know why.
